Static push-the-bit rotary guiding device

ABSTRACT

A static push-the-bit rotary guiding device includes: a mandrel having a central passage, wherein a circumferential groove is provided on an outer wall of the mandrel; a sleeve, which is sleeved in the circumferential groove and able to rotate independently; and a clutch, for cutting off or transferring a power from the mandrel to the sleeve. When it is unnecessary for the static push-the-bit rotary guiding device to provide a deviating force in a steady inclined section, a vertical section and a horizontal section, a rotational inertia and an interior energy storage of the rotary guiding device are not decreased, which is beneficial to highly-efficient and stable drilling of a downstream drill bit.

CROSS REFERENCE OF RELATED APPLICATION

This is a U.S. National Stage under 35 U.S.C 371 of the International Application PCT/CN2015/089713, filed Sep. 16, 2015, which claims priority under 35 U.S.C. 119(a-d) to CN 201410514459.3, filed Sep. 29, 2014.

BACKGROUND OF THE PRESENT INVENTION Field of Invention

The present invention relates to a technical field of petroleum drilling, and more particularly to a static push-the-bit rotary guiding device.

Description of Related Arts

In the field of drilling technology, the rotary steerable drilling system is widely applied. According to the requirement of trajectory control, during a rotary drilling process, the rotary steerable drilling system is able to adjust a well deviation and a direction in real-time, and has the advantages of high wellbore trajectory control precision, smooth drilled wellbore, low friction, low torque, large drilling ultimate displacement, little drilling accident, fast drilling speed, and low drilling cost. Thus, the rotary steerable drilling system is able to meet requirements of steerable drilling for the high-difficulty special-technology well such as the horizontal well, the extended-reach well, and the three-dimensional multi-target well.

An operating principle of the rotary steerable drilling system relies upon the biasing guiding mechanism of the rotary guiding device to actuate the drill bit or the drill column to make a directional deviation, thereby guiding a direction. According to different guiding manners, the rotary guiding device is divided into the push-the-bit rotary guiding device and the point-the-bit rotary guiding device. The push-the-bit rotary guiding device directly provides a lateral force for the drill bit at a position near the drill bit, while the point-the-bit rotary guiding device bends the drill column near the drill bit, so that the drill bit points to a wellbore trajectory control direction. Meanwhile, according to the operation manner of the biasing guiding mechanism, the rotary guiding device is divided into the static bias rotary guiding device and the dynamic bias rotary guiding device. The static bias rotary guiding device means the biasing guiding mechanism does not rotate with the drill column during the drilling process, so as to provide the lateral force at a fixed direction; and the dynamic bias rotary guiding device means the biasing guiding mechanism rotates with the drill column during the drilling process, and, relying on the control system, the biasing guiding mechanism directionally provides the guiding force at a certain position. However, because parts of performances of the static push-the-bit rotary guiding device are superior to that of the other rotary guiding device, the static push-the-bit rotary guiding device has gained the widespread use.

However, the conventional static push-the-bit rotary guiding device has a great disadvantage. Although the static push-the-bit rotary guiding device is able to provide the accurate and sufficient deviating force in the kick-off section, in the steady inclined section, the vertical section and the horizontal section, in which the rotary guiding device is unnecessary to provide the deviating force, the rotary guiding device has the decreased rotational inertia and the decreased interior energy storage, which is disadvantageous to highly-efficient and stable drilling of the drill bit, especially in the deep well and the extended-reach well.

SUMMARY OF THE PRESENT INVENTION

To solve the above problem, an object of the present invention is to provide a static push-the-bit rotary guiding device, whose rotational inertia and interior energy storage are not decreased when the rotary guiding device is unnecessary to provide a deviating force in a steady inclined section, a vertical section and a horizontal section, which is beneficial to highly-efficient and stable drilling of a drill bit.

The present invention provides a static push-the-bit rotary guiding device, comprising: a mandrel having a central passage, wherein a circumferential groove is provided on an outer wall of the mandrel; a sleeve, which is sleeved in the circumferential groove and able to rotate independently; and a clutch, for cutting off or transferring a power from the mandrel to the sleeve.

Preferably, the clutch comprises: a driving member and a driven member, which are arranged between the mandrel and the sleeve and for respectively actuating the mandrel and the sleeve to rotate; and a pushing unit, which is arranged in the sleeve and for actuating the driven member to separate from or connect with the driving member.

Preferably, the pushing unit comprises at least one linear motor or at least one clutch hydraulic cylinder which is able to be driven by a hydraulic power supply.

Preferably, the driving member and the driven member are two gears which mesh with each other, two splines which cooperate with each other, or two friction wheels which rub against each other.

Preferably, the driven member is fixed outside an end of the sleeve through a piston rod of the clutch hydraulic cylinder in the sleeve, and the driving member is fixed to a side wall of the circumferential groove, so that the piston rod of the clutch hydraulic cylinder is able to actuate the driven member to separate from or connect with the driving member after a stretch movement.

Preferably, a radial bearing is arranged between an inner wall of the sleeve and a bottom surface of the circumferential groove of the mandrel, two thrust bearings are respectively arranged between a left end of the sleeve and a left side wall of the circumferential groove, and between a right end of the sleeve and a right side wall of the circumferential groove, and both of the driving member and the driven member are located outside or inside a radial direction of the thrust bearings.

Preferably, the static push-the-bit rotary guiding device further comprises: a biasing guiding mechanism, for providing a lateral force; a measurement and control mechanism for controlling the biasing guiding mechanism and the clutch; and a power supply mechanism for providing an electric power.

Preferably, the biasing guiding mechanism comprises multiple swing ribs which are circumferentially arranged in an outer wall of the sleeve with an interval, for providing the required lateral force when guiding.

Further preferably, the biasing guiding mechanism further comprises a rib hydraulic cylinder, which is able to be driven by the hydraulic power supply and actuate the swing ribs to swing.

Preferably, the measurement and control mechanism comprises: a rib control unit which is connected between the hydraulic power supply and the rib hydraulic cylinder; a clutch control unit which is connected between the hydraulic power supply and the clutch hydraulic cylinder; a first pressure sensor for measuring a pressure of a fluid in the clutch hydraulic cylinder; and a second pressure sensor for measuring a pressure of a fluid in the rib hydraulic cylinder.

According to the present invention, the static push-the-bit rotary guiding device is able to cut off or transfer the power from the mandrel to the sleeve through the clutch. When guiding is required during the drilling process, the static push-the-bit rotary guiding device cuts off the power from the mandrel to the sleeve, and allows the sleeve not to rotate with the mandrel but keep still relative to a well wall, thereby ensuring the deviating force provided by the static push-the-bit rotary guiding device is accurate and sufficient, so that the drill bit makes a directional deviation smoothly. When guiding is not required during the drilling process, the static push-the-bit rotary guiding device transfers the power of the mandrel to the sleeve, actuates the sleeve to synchronously rotate with the mandrel, and has an increased rotational inertia and an increased energy storage, which is beneficial to highly-efficient and stable drilling of the drill bit.

According to the present invention, the static push-the-bit rotary guiding device has a simple and compact structure, a convenient machining, an easy assembling, and a safe and highly-efficient operation, which is easy for implementing popularization and application.

BRIEF DESCRIPTION OF THE DRAWINGS

The present invention is further illustrated in detail as follows, with a preferred embodiment and accompanying drawings.

FIG. 1 is a structural sketch view of a static push-the-bit rotary guiding device according to a preferred embodiment of the present invention.

FIG. 2 is a sketch view of a clutch and a mandrel of the static push-the-bit rotary guiding device according to the preferred embodiment of the present invention.

FIG. 3 is a sketch view of a hydraulic control of the static push-the-bit rotary guiding device according to the preferred embodiment of the present invention.

In the accompanying drawings, same elements are marked by the same reference characters. The accompanying drawings are not drawn according to an actual scale.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

The present invention is further described as follows with the accompanying drawings.

FIG. 1 shows a static push-the-bit rotary guiding device 100 (hereinafter referred to as rotary guiding device 100) provided by the present invention. The rotary guiding device 100 is able to actuate a drill bit or a drill column to make a directional deviation smoothly, thereby generating a guiding function.

According to the preferred embodiment of the present invention, an upstream is defined as a direction near a well mouth, and a downstream is defined as a direction away from the well mouth. The rotary guiding device 100 comprises a mandrel 12 having a central passage 12 a. An upstream end of the mandrel 12 (an end near a left side, as shown in FIG. 1), through a thread structure thereof, is able to connect with a drilling tool or a mud motor. A downstream end of the mandrel 12 (an end near a right side, as shown in FIG. 1), through a thread structure thereof, is able to connect with a drill pipe or an adapter of the drill bit. A circumferential groove 12 b is provided on an outer wall of the mandrel 12. The circumferential groove 12 b is preferred to be located at a center of the outer wall of the mandrel 12, and has two circular side walls and a bottom surface.

The rotary guiding device 100 further comprises a sleeve 14, which is sleeved in the circumferential groove 12 b and able to rotate independently. In order to mount the sleeve 14, the mandrel 12 is made up of two parts which are able to be separated from each other. A radial bearing (such as a deep groove ball bearing) is arranged between an inner wall of the sleeve 14 and the bottom surface of the circumferential groove 12 b of the mandrel 12, so as to allow the sleeve 14 to rotate independently. Meanwhile, a first thrust bearing 19 is arranged between an upstream end of the sleeve 14 and a left side wall of the circumferential groove 12 b, and a second thrust bearing 19 is arranged between a downstream end of the sleeve 14 and a right side wall of the circumferential groove 12 b, so as to provide an axial support for the mandrel 12, and enable the mandrel 12 to withstand a bit pressure and a weight of the drilling tool.

According to the present invention, the rotary guiding device 100 further comprises a clutch 18 which is able to cut off or transfer a power from the mandrel 12 to the sleeve 14. In order to guarantee that a conventional static push-the-bit rotary guiding device is able to provide an accurate and sufficient deviating force in a kick-off section, the mandrel thereof is designed to always rotate independently, relative to the sleeve. However, it is unnecessary for the rotary guiding device to provide the deviating force in a steady inclined section, a vertical section and a horizontal section, and the sleeve which does not rotate with the mandrel decreases a rotational inertia and an interior energy storage of the rotary guiding device, which is disadvantageous to highly-efficient and stable drilling of the drill bit, especially in a deep well and an extended-reach well. According to the present invention, the improved rotary guiding device 100 is able to cut off or transfer the power from the mandrel 12 to the sleeve 14 through the clutch 18. When guiding is required during a drilling process, the rotary guiding device 100 cuts off the power from the mandrel 12 to the sleeve 14, and allows the sleeve 14 not to rotate with the mandrel 12 but keep still relative to a well wall, thereby ensuring the deviating force provided by the rotary guiding device 100 is accurate and sufficient, so that the drill bit makes a directional deviation smoothly. When guiding is not required during the drilling process, the rotary guiding device 100 transfers the power of the mandrel 12 to the sleeve 14, actuates the sleeve 14 to synchronously rotate with the mandrel 12, and has an increased rotational inertia and an increased energy storage, which is beneficial to highly-efficient and stable drilling of the drill bit.

As shown in FIG. 2, the clutch 18 comprises: a driving member 21 and a driven member 20, which are arranged between the mandrel 12 and the sleeve 14; and a pushing unit 16, which actuates the driving member 21 to separate from or connect with the driven member 20. Through a separation or a connection between the driving member 21 and the driven member 20, the pushing unit 16 is able to cut off or connect the power between the mandrel 12 and the sleeve 14.

The pushing unit 16 comprises at least one linear motor, at least one hydraulic cylinder or at least one electromagnetic displacement mechanism. According to the preferred embodiment of the present invention, the pushing unit 16 comprises at least one clutch hydraulic cylinder 180 (as shown in FIG. 3), which is able to be driven by a hydraulic power supply 45. The clutch hydraulic cylinder 180 drives the driven member 20 to separate from or connect with the driving member 21, so as to cut off or connect the power between the mandrel 12 and the sleeve 14. Both of the driven member 20 and the driving member 21 are located outside or inside a radial direction of the thrust bearings 19. The driven member 20 and the driving member 21 are feasible to be two gears which mesh with each other, two splines which cooperate with each other, or two friction wheels which rub against each other.

It is noted that a space between the mandrel 12 and the sleeve 14 comprises an axial space (namely a space between the inner wall of the sleeve 14 and the bottom surface of the circumferential groove 12 b of the mandrel 12) and a radial space (namely a space between the upstream end of the sleeve 14 and the left side wall of the circumferential groove 12 b, and between the downstream end of the sleeve 14 and the right side wall of the circumferential groove 12 b). The driving member 21 and the driven member 20 are able to be arranged at the radial space or the axial space. When the driving member 21 and the driven member 20 are arranged at the radial space, the driven member 20 is fixed outside one end of the sleeve 14 through a piston rod of the clutch hydraulic cylinder 180 in the sleeve 14, and the driving member 21 is fixed to the corresponding side wall of circumferential groove 12 b, so that the piston rod of the clutch hydraulic cylinder 180 is able to actuate the driven member 20 to separate from or connect with the driving member 21 after a stretch movement. When the driving member 21 and the driven member 20 are arranged at the axial space, the driving member 21 is feasible to be a convex part, which is able to be pushed along a radial direction by the piston rod of the clutch hydraulic cylinder 180 in the sleeve 14, so that the driving member 21 enters a concave (namely the driven member 20) formed on the bottom surface of the circumferential groove 12 b, thereby realizing the separation or the connection between the driven member 20 and the driving member 21.

According to the present invention, the static push-the-bit rotary guiding device 100 further comprises: a biasing guiding mechanism 30, for providing a lateral force; a measurement and control mechanism 40, for controlling the biasing guiding mechanism 30 and the clutch 18; and a power supply mechanism, which provides an electric power for the rotary guiding device 100. The power supply mechanism is well known to one skilled in the art and thus not described in detail.

The biasing guiding mechanism 30 comprises multiple swing ribs 17 which are circumferentially arranged in an outer wall of the sleeve 14 with an interval. After swinging, ends of the swing ribs 17 are able to lean against the well wall, so as to provide the lateral force. In order to actuate the swing ribs 17, the biasing guiding mechanism 30 further comprises a rib hydraulic cylinder 170, which is able to be driven by the hydraulic power supply 45 and actuate the swing ribs 17 to swing. It is feasible to replace the rib hydraulic cylinder 170 by the linear motor or the electromagnetic displacement mechanism. Compared with the linear motor and the electromagnetic displacement mechanism, the rib hydraulic cylinder 170 is able to provide a larger lateral force. It is feasible that the hydraulic power supply 45 for driving the rib hydraulic cylinder 170 and the hydraulic power supply 45 for driving the clutch hydraulic cylinder 180 are the same one, and the hydraulic power supply 45 is preferred to be a hydraulic pump connected to a fuel tank. Accordingly, a structure thereof becomes simple and compact, which facilitates machining and processing, and saving a cost.

As shown in FIG. 3, the measurement and control mechanism 40 comprises a rib control unit 171 connected between the hydraulic power supply 45 and the rib hydraulic cylinder 170, so that the measurement and control mechanism 40 is able to control a swing degree of the swing ribs 17 accurately and in real-time, thereby providing the required lateral force when guiding. The measurement and control mechanism 40 further comprises a clutch control unit 181 connected between the hydraulic power supply 45 an the clutch hydraulic cylinder 180, so that the measurement and control mechanism 40 is able to control a separation and a connection of the clutch 18 in real-time. The rib control unit 171 and the clutch control unit 181 are well known to one skilled in the art and thus not described in detail.

For more accurately controlling the clutch 18 and the swing ribs 17, the measurement and control mechanism 40 further comprises a first pressure sensor 41 for measuring a pressure of a fluid in the clutch hydraulic cylinder 180, and a second pressure sensor 42 for measuring a pressure of a fluid in the rib hydraulic cylinder 170. Thus, the measurement and control mechanism 40 is able to monitor and adjust the swing degree of the swing ribs 17 and a working condition of the clutch 18 in real-time.

The measurement and control mechanism 40 further comprises a three-axis acceleration sensor, a measurement processing circuit, a motor driver, and a controller 46. The three-axis acceleration sensor is for detecting a spatial attitude of the rotary guiding device 100, comprising a well deviation angle at a position where the rotary guiding device 100 is located and a tool face angle of each swing rib 17. Through the controller 46, a three-axis accelerometer and each pressure sensor rapidly calculate, and the spatial attitude of the rotary guiding device 100 and a strength of a hydraulic pressure withstood by each swing rib 17 are obtained. The controller 46 also monitors a working condition of hydraulic power supply 45 in real-time. According to a strength of a hydraulic pressure of the rib hydraulic cylinder 170, through a corresponding control algorithm, the controller 46 adjusts the hydraulic power supply 45, and respectively actuates the swing ribs 17 to swing correspondingly. The three-axis acceleration sensor, the measurement processing circuit, the motor driver and the controller 46 are all well known to one skilled in the art and thus not described in detail.

An operating principle of the static push-the-bit rotary guiding device 100 provided by the present invention is described as follows. After turning on the rotary guiding device 100, the controller 46 of the measurement and control mechanism 40 through the clutch control unit 181 controls the clutch 18 to cut off the power from the mandrel 12 to the sleeve 14, and then through the rib control unit 171 controls the rib hydraulic cylinder 170 to respectively actuate the swing ribs 17 to swing correspondingly, so as to provide the lateral force required by guiding. After finishing guiding, the controller 46 through the clutch control unit 181 controls the clutch 18 to transfer the power from the mandrel 12 to the sleeve 14, which actuates the sleeve 14 to synchronously rotate with the mandrel and increase the rotational inertia and the energy storage of the rotary guiding device 100, thereby being beneficial to highly-efficient and stable drilling of the drill bit.

According to the present invention, when it is unnecessary for the static push-the-bit rotary guiding device 100 to provide the deviating force in the steady inclined section, the vertical section and the horizontal section, the rotational inertia and the interior energy storage of the rotary guiding device 100 are not decreased, which is beneficial to highly-efficient and stable drilling of the downstream drill bit.

Although the present invention has been described with reference to the preferred embodiment, within a scope of the present invention, various modifications can be made, and it is feasible to use the equivalent to replace the part described in the present invention. In particular, as long as no structure conflict exists, technical features mentioned in the preferred embodiment can be combined in any manner. The present invention is not limited to the disclosed preferred embodiment in the specification, but includes all technical schemes within the scope of the following claims. 

1.-10. (canceled) 11: A static push-the-bit rotary guiding device, comprising: a mandrel having a central passage, wherein a circumferential groove is provided on an outer wall of the mandrel; a sleeve, which is sleeved in the circumferential groove and able to rotate independently; and a clutch, for cutting off or transferring a power from the mandrel to the sleeve. 12: The static push-the-bit rotary guiding device, as recited in claim 11, wherein the clutch comprises: a driving member and a driven member, which are arranged between the mandrel and the sleeve and for respectively actuating the mandrel and the sleeve to rotate; and a pushing unit, which is arranged in the sleeve and for actuating the driven member to separate from or connect with the driving member. 13: The static push-the-bit rotary guiding device, as recited in claim 12, wherein the pushing unit comprises at least one linear motor or at least one clutch hydraulic cylinder which is able to be driven by a hydraulic power supply. 14: The static push-the-bit rotary guiding device, as recited in claim 13, wherein the driving member and the driven member are two gears which mesh with each other, two splines which cooperate with each other, or two friction wheels which rub against each other. 15: The static push-the-bit rotary guiding device, as recited in claim 14, wherein: the driven member is fixed outside an end of the sleeve through a piston rod of the clutch hydraulic cylinder in the sleeve, and the driving member is fixed to a side wall of the circumferential groove, so that the piston rod of the clutch hydraulic cylinder is able to actuate the driven member to separate from or connect with the driving member after a stretch movement. 16: The static push-the-bit rotary guiding device, as recited in claim 12, wherein: a radial bearing is arranged between an inner wall of the sleeve and a bottom surface of the circumferential groove of the mandrel; two thrust bearings are respectively arranged between a left end of the sleeve and a left side wall of the circumferential groove, and between a right end of the sleeve and a right side wall of the circumferential groove; and both of the driving member and the driven member are located outside or inside a radial direction of the thrust bearings. 17: The static push-the-bit rotary guiding device, as recited in claim 13, wherein: a radial bearing is arranged between an inner wall of the sleeve and a bottom surface of the circumferential groove of the mandrel; two thrust bearings are respectively arranged between a left end of the sleeve and a left side wall of the circumferential groove, and between a right end of the sleeve and a right side wall of the circumferential groove; and both of the driving member and the driven member are located outside or inside a radial direction of the thrust bearings. 18: The static push-the-bit rotary guiding device, as recited in claim 14, wherein: a radial bearing is arranged between an inner wall of the sleeve and a bottom surface of the circumferential groove of the mandrel; two thrust bearings are respectively arranged between a left end of the sleeve and a left side wall of the circumferential groove, and between a right end of the sleeve and a right side wall of the circumferential groove; and both of the driving member and the driven member are located outside or inside a radial direction of the thrust bearings. 19: The static push-the-bit rotary guiding device, as recited in claim 15, wherein: a radial bearing is arranged between an inner wall of the sleeve and a bottom surface of the circumferential groove of the mandrel; two thrust bearings are respectively arranged between a left end of the sleeve and a left side wall of the circumferential groove, and between a right end of the sleeve and a right side wall of the circumferential groove; and both of the driving member and the driven member are located outside or inside a radial direction of the thrust bearings. 20: The static push-the-bit rotary guiding device, as recited in claim 13, wherein the static push-the-bit rotary guiding device further comprises: a biasing guiding mechanism, for providing a lateral force; a measurement and control mechanism for controlling the biasing guiding mechanism and the clutch; and a power supply mechanism for providing an electric power. 21: The static push-the-bit rotary guiding device, as recited in claim 15, wherein the static push-the-bit rotary guiding device further comprises: a biasing guiding mechanism, for providing a lateral force; a measurement and control mechanism for controlling the biasing guiding mechanism and the clutch; and a power supply mechanism for providing an electric power. 22: The static push-the-bit rotary guiding device, as recited in claim 19, wherein the static push-the-bit rotary guiding device further comprises: a biasing guiding mechanism, for providing a lateral force; a measurement and control mechanism for controlling the biasing guiding mechanism and the clutch; and a power supply mechanism for providing an electric power. 23: The static push-the-bit rotary guiding device, as recited in claim 20, wherein: the biasing guiding mechanism comprises multiple swing ribs which are circumferentially arranged in an outer wall of the sleeve with an interval, for providing the required lateral force when guiding. 24: The static push-the-bit rotary guiding device, as recited in claim 21, wherein: the biasing guiding mechanism comprises multiple swing ribs which are circumferentially arranged in an outer wall of the sleeve with an interval, for providing the required lateral force when guiding. 25: The static push-the-bit rotary guiding device, as recited in claim 22, wherein: the biasing guiding mechanism comprises multiple swing ribs which are circumferentially arranged in an outer wall of the sleeve with an interval, for providing the required lateral force when guiding. 26: The static push-the-bit rotary guiding device, as recited in claim 23, wherein: the biasing guiding mechanism further comprises a rib hydraulic cylinder, which is able to be driven by the hydraulic power supply and actuate swing ribs to swing. 27: The static push-the-bit rotary guiding device, as recited in claim 24, wherein: the biasing guiding mechanism further comprises a rib hydraulic cylinder, which is able to be driven by the hydraulic power supply and actuate swing ribs to swing. 28: The static push-the-bit rotary guiding device, as recited in claim 25, wherein: the biasing guiding mechanism further comprises a rib hydraulic cylinder, which is able to be driven by the hydraulic power supply and actuate swing ribs to swing. 29: The static push-the-bit rotary guiding device, as recited in claim 26, wherein the measurement and control mechanism comprises: a rib control unit which is connected between the hydraulic power supply and the rib hydraulic cylinder; a clutch control unit which is connected between the hydraulic power supply and the clutch hydraulic cylinder; a first pressure sensor for measuring a pressure of a fluid in the clutch hydraulic cylinder; and a second pressure sensor for measuring a pressure of a fluid in the rib hydraulic cylinder. 30: The static push-the-bit rotary guiding device, as recited in claim 28, wherein the measurement and control mechanism comprises: a rib control unit which is connected between the hydraulic power supply and the rib hydraulic cylinder; a clutch control unit which is connected between the hydraulic power supply and the clutch hydraulic cylinder; a first pressure sensor for measuring a pressure of a fluid in the clutch hydraulic cylinder; and a second pressure sensor for measuring a pressure of a fluid in the rib hydraulic cylinder. 